Thinking about it, I'm not sure why this would make a huge difference, since all you'd end up with is a de-DRMed ePub, and the iBooks selection isn't as good as you can find at B&N or Google Books. As it is, you can already get the iBooks UI experience with de-DRMed epubs from those two stores, if that's what floats your boat.

It's good to have portability and more bookstores to choose from, but right now, I'm just not feeling it.